Financing Agreements (Schedule of Covenants) (Details)	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Maximum [Member]
Debt Instrument [Line Items]
Secured Net Leverage Ratio					4.75
Maximum [Member] | Scenario, Forecast [Member]
Debt Instrument [Line Items]
Secured Net Leverage Ratio	3.00	3.50	4.00	4.50
Minimum [Member]
Debt Instrument [Line Items]
Interest Coverage Ratio					3.25
Minimum [Member] | Scenario, Forecast [Member]
Debt Instrument [Line Items]
Interest Coverage Ratio	4.00	3.75	3.50	3.25